IF I planned to keep the vehicle indefinitely, i.e., drive the wheels off of it (not letting it sit for more than a weekend - daily driving - 12K+/year), I would absolutely buy new without hesitation. Period. Not even a slight doubt in my mind.

IF I planned to keep it less than 5 years, I would sell it now for KBB minus the cost of a GreenBean and be done with it.

Anyone with any decent mechanical skill and can follow directions on Youtube can replace individual cells that are weak for like $25 each cell. Yes there are lots of connections and yes there are steps to balance the cells etc, but why replace cells that are perfectly fine. Some NiMh cells last almost forever if conditioned right and some are weak and fail. Ask all the RC people. Are packs are the same way. Just have to have the patience to find out which one is bad and do all the steps. Anyone else do this?

Anyone with any decent mechanical skill and can follow directions on Youtube can replace individual cells that are weak for like $25 each cell. Yes there are lots of connections and yes there are steps to balance the cells etc, but why replace cells that are perfectly fine. Some NiMh cells last almost forever if conditioned right and some are weak and fail. Ask all the RC people. Are packs are the same way. Just have to have the patience to find out which one is bad and do all the steps. Anyone else do this?

This is a commonly held misconception. The best analogy is an 18 wheeler with bald tires. One blows. It's brought into the shop with wheel covers on that can't be removed easily without specialized expensive equipment, and the only measurement one can take is tire pressure. The one bad one is obvious (this time). It is replaced and sent on its way. What is the expectation of longevity?

There are many accounts of this on YouTube. When the longevity is tested, the longest last a little over a year. Many are frequently into the packs repeating the same procedure within 3-6 months or less.

Here is a Prius pack that threw a P0A80 and sat for about a month. Which modules would you replace for a reliable repair (greater than 1 year)?

The red bars are the PRE-reconditioning. The green bars as POST-reconditioning. The RED bars are more indicative of how they will perform if you just swap them out based on voltage alone. The green bars are how they will perform if you recondition them.

The colored zones reflect how long I would expect them to last.

Note how 11 of the green bars are UNDER the 4000mAh line. Anything below this is going to be unreliable and will look like a game of whack-a-mole with you breaking down the pack every 3-6 months (at best).

Modules in the red zone will likely not work for any significant period of time. The car will see them as such low capacity, they will code P0A80 for deterioration.